Broach.



J. A. EDEN, JR.

BROACH. APPLICATION FILED MAYIG. 1911.

r 1,275,006. Patented Aug. 6,1918

' 3 J 1. I Z j (V 3 K J r I JAMES A. EDEN, JR.,*OF SPRINGFIELD,MASSACHUSETTS, ASSIG-NOR,

BY MESN'E ASSIGN- MENT S, TO JOHN OAKLEY, OF SPRINGFIELD, MASSACHUSETTS.

' BBOACH.

Specification of Letters Patent. I Patented Aug. 6, 1918.

Application flledlMay 16,1917. Serial No. 1es,94s.- 5

To all whom it may concern.-

Be it known that I, JAMES A. EDEN, Jr.,-

a citizen of the United States, residing in Springfield, Massachusetts,have inventedcertain new and useful. Improvements in;

Broaches, of which the following is a specification.

.My invention aims to rovide a breach which shall be more easllyoperated and more durable than previous broaches and which shall havefurther advantages referred to in detail hereinafter.

The accompanying drawings illustrate embodiments of the invention.

Figure 1 is a side elevation of a broach, partly broken away;

Fig. 2 is a section of the same on the line 22 of Fig. 1;

Figs. 3 and 4 respectively are a plan and end view of the pulling head;

Fig. 5 is a plan of one of the side members;

Figs. 6 and 7 are respectively'a side elevation and face elevation ofone of the teeth of Fig. 1; v

Fig. 8 is a cross section and Fig. 9 a longitudinal section of anotherstyle of construction;

Fig. 10 is a plan of one ofthe halves of another style of constructionand Fig. 11 is a side elevation of the same;

Fig. "12 is a plan of a portion of a com pleted broach made up of partslike Fig. 10; Fig. 13 is a plan of a construction similar to Fig. 12 butwith a slight modification;

Fig. '14 is a plan of a still further modified construction;

Fig.. 15 is a transverse section of Fig. 14;

Fig. 16 is a separated view of one of the side members of Fig. 15;

Fig. 17 is a cross section of another modification, taken on the line1717 of Fig. 18, and Fig. 18, is a side elevation of the cutters inplace against one ofthe side members;

Fig. 19 is a plan of one of the'cutters of Figs. 17 and 18;

Figs. 20 and 21 areplans of other modifi-.

cations; Fig. 21 being partly in section on the line 2'121 ofFig. 22;

Fig. 22 is a side elevation of the construetion of Fig. 21;

Fig. .23 is a plan of another modification,

and Fi 24 is a side elevation of the cutters of Fig. 23 in' place; someof the cutters and the invention is attaching a puller to the broach.

The invention, in'its principal features of novelty,.is applicable. tobroaches of various old styles. But the designs shown are of.

the style described in Oakley Patent No.

1,121,126 of December 15, 1 914 in which there is a longitudinal passageopen along one side of the broach and communicating withlateral-passages between the cutters located at the opposite side of thebroach, preferably used in this form. Referring to the embodiments ofthe invention illustrated, and first to Figs. 1 to 7 inclusive, thebroach comprises two side members A with teeth B between them the endsof which constitute cutters of the usual or any suitable size andinclination. The parts are mounted on a head G carrying an externallythreaded end D adapted to be fastened to the usual puller for pullingthe broach through the work. The side members A are provided withgrooves E shaped and directed to embrace the teeth B. The latter extenddownward to a point slightly above the lower edges of the side membersso as to leave a clear longitudinal passage for the" chips which willmove down between the teeth and curling forward will strike the rearface of the forward tooth and be deflected and pass out roughly in thedirec tion of the arrow F. The teeth are prefer.

ably fastened against longitudinal movement in their grooves by means ofpins or rivets G. The exposed end of each tooth B is reduced in width asindicated at B (Fig. 2) so as to cutfa chip or shaving which will be ofless width than the passage through the broach and will move easilythrough such passage.

The head or end member is fastened to the side members in a mannersimilar to the teeth. It has an extension H which lies be tween the sidemembers, with a vertical rib 'J on its side entering correspondinggrooves in the side members, and a pin or rivet K holds thepartsftogether.

Referring to .Figs.'8 and 9,the teeth B are formed with lateral bosses Lwhich fit within similar sockets in the'insido face of the" sidemembers, and a pair 'of pins' G (or, a

single pin through either of the bosses would be sufficient for mostwork) is used for fasplace. The side the side members has the advantagethat the teeth can be 'made of a higher grade of steel or a grade whichis better adapted for outting, while the side members can be made of atougher steel better adapted to resist the pulling strain and not sobrittle as the tool steel used for the teeth. It has also the advantagethat if a single tooth-is broken or damaged it can be replaced withoutscrapping any of the other parts, and all the teeth when worn out may bereplaced by new ones, using the same side members. But the invention mayalso be embodied in a construction in which the teeth are not formedseparately from the side members.

Figs. 10, 11 and 12 show side members A with teeth B formed integrallyon the inner faces thereof. Each side is, preferably, formed with onehalf of the total number of teeth, the teeth on one side being staggeredwith relation to those on the other side when the parts are assembledas-in Fig.

12. The two members may be fastened together by means of pins as in Fig.1, or such fastenings may be omitted, the parts being embraced and heldtogether as they pass through the hole in the work piece which is beingbroached. The two halves in this case would be made of high grade ortool steel such as is used for the separate teeth in the otherconstructions described. This construction simplifies the manufacture ofthe broach. I

. For maintaining the two halves more rigidly. in correct relation toeach other, they may be made as in Fig. 13, the teeth B being wider thanthe space between the side members and their free side edges fittingwithin ooves E on the opposite side member, Figs. 14, 15 and 16illustrate another way of holding the teeth in place and at the sametime holding them in engagement with the opposite side members. Eachside member is formed with grooves E having undercut shoulders M attheir edges which engage similarly shaped overhanging plpertions of theteeth .B. Also the side mem rs A are formed with lugs Non their innerfaces ggainst which the lower ends of the teeth ear.

Figs. 17, 18 and 19 illustrate a design which simplifies theconstruction of the side members, the teeth being provided with projections-which hold them in place. The side members A are formed withcontinuous longitudinal rectangular grooves O on their inner faces. Eachtooth B is provided on each of its side faces with a wing P fitting inthe groove 0 of the adjacent side membe cheaply made case are made by asimple slot milling operation. A stop of course is necessary at the backend of the broach to prevent the teeth from backward movement relativeto the side members.

Fig. 20 shows a construction similar to Fig. 14 except that there is arectangular, instead of an overhanging, engagement of the teeth B withthe grooves E, or rather with the ribs Q- on the inner faces of the sidemembers A.

In Figs. 21 and 22 the backs of the teeth B bear against ribs It on theinner faces of the side members A, pins G being used for holding theparts together. Each tooth has a rearwardly extending tail S extendingbackward beyond the adjacent ribs B, so that a chip passing down betweenthe teeth will bear against such tails S, which are of harder materialgenerally than the side members and will resist longer the abrasiveeffect of the passing chips. It' is generally preferable to use aconstruction in which the chip will pass between faces of hard steel,for thereason stated.

In Figs. 23 and 24, the teeth B bear against ribs T formed on the innerfaces of the side members A and the ribs T are of such depth as to meetacross the intervening space. This sacrifices the advantage above'referred to of a hard metal face to receive the abrasion of the passingchip. But it has the advantage that the two half members may be fastenedtogether by a single rivet or other means without the interposition ofthe teeth and may be turned to the perfectly cylindrical shape requiredbefore inserting the teeth. In the other constructions illustrated, inwhich the side members do not contact with each other, it is necessaryto introduce fillers of the exact width of the teeth, but notprojecting, between the side members to hold them accurately spacedwhile they are being turned to the exact cylindrical size required. Inthe construction of Figs. 23 and 24 the teeth may be held in placeeither by means of pins or rivets G as before described, or by means oflugs U on their rear faces adapted to bear ,on the tops of theribs T ofthe side mem:

bers; or by both meansif desired.

-Fig. 25 shows a style of puller head differing slightly from that ofFig. 1. The side members A and teeth B belng assembled, a sleeve V isscrewed on the externally threaded end of the assembled side mem- 1hers, being provided with an internal thread understood therefrom thatthe invention is 'W- on its free end for attachment to the machine.

' ThoughI have described with great particularity of detail certain-specific embodiments of my.invention, yet, it is not tobe restrictedto. the specific constructions illustrated. Various modificationsthereof in detail and in the arrangement and manner of combiningthese-partsmay be made by those skilled in '"the art without" departing.from' the invention as defined in the following broach teeth arranged ina row between said side comprising longitudinally straight sidemembersand separately formed members, the broach thus formed havinginterior chip passages which have faces formed by the faces of theteeth.

members which are segmental in cross-section and have lateral grooves intheir inner faces, teeth located in said grooves and means for holdingthe teeth firmly against movement in said grooves.

5. A broach made in a plurality. of side members which are segmental incross-section and detachably fastened together and teeth held betweensaid side members.

6. A broach made in a plurality of side 1 V 4. A-broach made in aplurality of side members which are segmental in cross-section, teethbetween said side members, andv it) pulling head fastened to both; sidememers.

7. A broach having separately formed teeth and having'chip passages,which passages have faces .formed by the faces of the teeth, said broachhaving a' longitudinal passage communicating with the passages betweensaid teeth.

In witness whereof, I have ;hereunto signed my name.

' JAMES A. EDEN, JR.

